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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
531

A decision support system for multi-objective forest management : a study in the Queen Elizabeth National Forest Park in Scotland

Kazana, Vasiliki January 1989 (has links)
No description available.
532

Demand based price determination for electricity consumers in private households

Borggren, Lisa, Grill, Rebecca, Lykken, Susanna, Nilsson, Maria January 2016 (has links)
This report investigates the effects a demand based tariff would have on private electricity consumers and how it could contribute to a sustainable electrical grid. The fuse tariff that is currently used charges customers for their electricity usage and does not fully reflect the electrical grid load and thereby not the cost for the distribution system operators. A demand based tariff, that charges customers for their power peaks and promotes a change of behaviour better reflects the grid load and could lead to a more even grid distribution and a sustainable development. In light of this issue, two demand based tariffs have been constructed for the energy company Upplands Energi’s private customers’ current electricity consumption. One of the tariffs consists of a higher fixed cost and a lower variable cost and the other consists of a lower fixed cost and a higher variable cost, both leading to the same revenue för Upplands Energi. The two different demand based tariffs have been simulated and analysed, where the one with the lowest fixed cost is recommended since it gives customers higher economic incentives to change their electricity usage behaviour. It is essential that electricity retailers communicate the information of how the demand based tariff works to the customers in order to make them change their electricity behaviour to attain a sustainable grid.
533

Mind the Gap : exploring evidence-based policymaking for improved preventive and mental health services in the Swedish health system

Richter Sundberg, Linda January 2016 (has links)
Background: The challenges in the utilization of scientific findings in the fields of prevention and mental health are well documented. Scholars have found significant gaps between the knowledge available and the knowledge applied in healthcare. Studies have suggested that about half of the patients receive the recommended care for their medical condition. In order to address this gap, health systems at global, national, regional and local levels have made diverse efforts to facilitate the uptake of research for example through evidence-based health policy processes. In Sweden, government agencies and health policy actors such as the National Board of Health and Welfare support and control the health care system through evidence-based policies amongst other steering tools. The overall aim of this thesis is to explore evidence-based policy processes, and to further understand barriers to implementation of policies in the fields of preventive and mental health services. Methods: A multiple case study approach was used, and data were collected from several sources. Qualitative content analysis methodology was used. Case 1 comprises the development and early implementation of national guidelines for methods of preventing disease managed by the National Board of Health and Welfare during 2007–2014. Case 2 covers the effort to improve health care for the older population that was undertaken through an agreement between the Swedish government and the Swedish Association of Local Authorities and Regions during 2009–2014. Case 3 involves an effort to implement an adapted version of a systematic review from the Swedish agency for health technology assessment and assessment of social services on treatment of depression in primary health care. Data was collected between 2007 and 2010. In Paper 1, the policies from Case 1 and 2 were studied using a longitudinal, comparative case study approach. Data were collected through interviews, documents and observations. A conceptual model was developed based on prior frameworks. The model was used to organize and analyse the data. In Paper 2, the guideline development process (Case 1) was studied through interviews and the collection of documents. A prior framework on guideline quality was used in order to organize the data. Paper 3 investigated decision-making processes during guideline development using a longitudinal approach. Qualitative data were collected from questionnaires, documents and observations and analysed using conventional and summative content analysis. In Paper 4, the barriers to implementation were investigated through interviews and the collection of documents. Data were analysed using qualitative content analysis with a conceptual model to structure the analysis. Results: The sources and procedures for policy formulation differed in Case 1 and 2, as did the approaches to promote the implementation of the policies. The policy processes were cyclical, and phases overlapped to a large degree. The policy actors intended to promote implementation, both during and after the policy formulation process. The thesis shows variation in how the key policy actors defined and used research evidence in the policy processes. In addition, other types of knowledge (e.g. politics, context, experience) served as alternative or multiple sources to inform the health policies. The composition of sources that informed the policies changed over time in Cases 1 and B. During the policy formulation and implementation process, efforts to integrate research evidence with clinical experiences and values were associated with tension and recurrent dilemmas. On the local level (i.e. primary health care centres), barriers to implementation were found related to the innovation and among health professionals, patients, in social networks as well as in the organizational, economic and political contexts. Conclusion: The concept of evidence holds a key position in terms of goals and means for knowledge based policymaking in the Swedish health system. Broad definitions of evidence – including research and non-research evidence - were requested and to various extents utilized by the policy actors in the studied cases. An explicit terminology and systematic, transparent methodology to define, identify, and assess also non-research evidence in policy processes would potentially strengthen the clarity and validity of these processes and also enhance policy implementation. Particular determinants to implementation, such as the interventions characteristic, are to a considerable degree established early in the policy process, during agenda setting and policy formulation. This early phase offers unique opportunities to assess and build capacity, initiate and facilitate implementation. Early analysis and considerations of target populations and contexts and other implementation determinants related to the specific policy scope (e.g. disease preventive guidelines) could enhance the forth-coming implementation of the policy.
534

Computer-based sketching and the productivity of the conceptual stage of design

Mustafa, Janan Abdulsattar January 2013 (has links)
Many designers find computer-based tools are not as effective during the early stages of design as manual sketching. However, to abandon the computer in these conceptual stages denies designers the computer‟s capability to translate and supplement imaginative design thinking. Recent design studies address conceptual design. What is the impact of computer-based drawing and sketching on designers‟ cognition and productive reasoning? This research focuses on the relationship between the characteristics of sketching using the drawing environment of the computer and the productivity of the conceptual design phase. I provide a theoretical framework that identifies and clarifies both sketching and productivity. Previous specialized studies are selective and sometimes only descriptive in defining this relationship. A review of these studies reveals a gap in our understanding of those aspects of sketching that relate to visualization, imagination and the generation of design ideas. The thesis addresses three objectives: (i) to build a comprehensive theoretical framework that on one hand defines the characteristics of sketching that might affect the generation of design ideas, and on the other hand defines the productivity of conceptual design and its indicators; (ii) to apply this framework in a practical study; and (iii) to extract implications for the relationship. To address the problem of computer-based sketching, I indentify the continuity within the dynamic field of images usually generated while designers sketch as the most effective characteristic of the computer sketching process. I establish a measure of continuity defined by (i) the degree of ease in projecting design images, (ii) the degree of continuity of displaying images due to changing the status of the design objects and due to navigation around the objects, (iii) the degree of provision of a holistic view (i.e., the total view of the design objects on the computer screen). Then I define productivity within this framework in terms of the cognitive operations of dialogical reinterpretation. When sketching, designers seem to perform key operations such as interpreting, reframing and restructuring. I present the case that a process rich with these cognitive operations is productive. The study makes use of the fields of free hand sketching, literature, cognitive psychology and Gestalt theory. Four indicators emerge from this study: the occurrence of pattern discovery, conceptual reinterpretation, alternation of thinking, and restructuring. I identify key variables that define the degree of continuity of the dynamic field of images which relate to designer‟s performance to verify their relationship with productivity. I study ten design participants who are given a design task that involves sketching with various CAD systems. The study involves 21 hours of recorded video analyzed using a method adapted from Goldschmidt's “linkography” tool for representing design protocols. I identify where patterns of relationships between variables exist, and where they do not apply. Not all the selected variables of continuity of the dynamic field of images, nor all the indicators of productivity in the conceptual design phase, support these patterns of relationships. This indicates that there is a special group of characteristics of sketching that maintain the pace of continuity within the dynamic field of images can improve the productivity in the conceptual phase.
535

A knowledge acquisition tool to assist case authoring from texts

Asiimwe, Stella Maris January 2009 (has links)
Case-Based Reasoning (CBR) is a technique in Artificial Intelligence where a new problem is solved by making use of the solution to a similar past problem situation. People naturally solve problems in this way, without even thinking about it. For example, an occupational therapist (OT) that assesses the needs of a new disabled person may be reminded of a previous person in terms of their disabilities. He may or may not decide to recommend the same devices based on the outcome of an earlier (disabled) person. Case-based reasoning makes use of a collection of past problem-solving experiences thus enabling users to exploit the information of others’ successes and failures to solve their own problem(s). This project has developed a CBR tool to assist in matching SmartHouse technology to the needs of the elderly and people with disabilities. The tool makes suggestions of SmartHouse devices that could assist with given impairments. SmartHouse past problem-solving textual reports have been used to obtain knowledge for the CBR system. Creating a case-based reasoning system from textual sources is challenging because it requires that the text be interpreted in a meaningful way in order to create cases that are effective in problem-solving and to be able to reasonably interpret queries. Effective case retrieval and query interpretation is only possible if a domain-specific conceptual model is available and if the different meanings that a word can take can be recognised in the text. Approaches based on methods in information retrieval require large amounts of data and typically result in knowledge-poor representations. The costs become prohibitive if an expert is engaged to manually craft cases or hand tag documents for learning. Furthermore, hierarchically structured case representations are preferred to flat-structured ones for problem-solving because they allow for comparison at different levels of specificity thus resulting in more effective retrieval than flat structured cases. This project has developed SmartCAT-T, a tool that creates knowledge-rich hierarchically structured cases from semi-structured textual reports. SmartCAT-T highlights important phrases in the textual SmartHouse problem-solving reports and uses the phrases to create a conceptual model of the domain. The model then becomes a standard structure onto which each semi-structured SmartHouse report is mapped in order to obtain the correspondingly structured case. SmartCAT-T also relies on an unsupervised methodology that recognises word synonyms in text. The methodology is used to create a uniform vocabulary for the textual reports and the resulting harmonised text is used to create the standard conceptual model of the domain. The technique is also employed in query interpretation during problem solving. SmartCAT-T does not require large sets of tagged data for learning, and the concepts in the conceptual model are interpretable, allowing for expert refinement of knowledge. Evaluation results show that the created cases contain knowledge that is useful for problem solving. An improvement in results is also observed when the text and queries are harmonised. A further evaluation highlights a high potential for the techniques developed in this research to be useful in domains other than SmartHouse. All this has been implemented in the Smarter case-based reasoning system.
536

Model-based Simulation Training Supporting Military Operational Processes

Sennersten, Charlotte January 2010 (has links)
In military training contexts, fast and long term decisions are intermixed where survival and security are prioritized. Simulation-based training, here applied to ground patrols in Afghanistan, can provide preparation for mission critical and life critical operations prior to exposure to real danger. Optimising the effectiveness of simulation-based training raises the need for more detailed representations of the competences required, both for simulation design and for evaluating simulation effectiveness. These needs are here considered in terms of three research questions . The first research question asks how objects trigger dialogue in observational tasks. Eye gaze tracking and recorded dialogue provide a foundation for proposing the cognitive operational structures behind how objects and dialogue are structured when people work together when collaborating in simulation-based training sessions. The objects are tracked along with related observational tasks and the communication between people in a team in ground vehicles and in the Tactical Operations Centre (TOC). The second research question asks how the results of simulation-based training for emergency situations can be described and evaluated. The last research question asks how debriefing and learning create and refine cognitive comprehension, the competency developed in a group. Low level visual cognition in a tactical environment is explored using an eye gaze tracking system integrated with a simulation environment. The integrated system has been evaluated, its accuracy characterized, and the system was then used to evaluate hypotheses related to visual queuing and target selection. The research questions are then explored more broadly based upon two exploratory field studies of simulation-based training sessions held for military staff before leaving for ISAF in Afghanistan. Study methods here include eye gaze tracking, video and audio recording, behavioral observation and retrospective questions. The field studies were conducted at the Swedish Life Guard Regiment sub-departments: International Training Unit(IntUtbE), pre-deployment training for Peace support operations, and Swedish Armed Forces International Centre (SWEDINT), with their Simulation, Modeling and Practical Platform. Based upon data obtained in the field studies, cognitive models of decision processes involved in operational task performance are developed to provide a basis for answering the research questions. Cognitive modelling begins with the Belief, Desire and Intension (BDI) model. This model is then modified in several steps to cover different levels of decision making revealed by the field studies, including an intrapersonal and organizational layer, an educational layer, a layer where objects are build into the algorithm as a basis for purposive behavior, and finally a team competency layer built largely during debriefing sessions. These models can be used to evaluate simulation-based training effectiveness, to provide feedback both in real time and retrospectively to trainees and teams, and potentially could be used in operational systems to provide real-time information about individual and group state during operations, for decision enhancement, and potentially as elements of the implementation of automated operational forces.
537

Synthesis and characterization of nanostructured palladium-based alloy electrocatalysts

Sarkar, Arindam 22 October 2009 (has links)
Low temperature fuel cells like proton exchange membrane fuel cells (PEMFC) are expected to play a crucial role in the future hydrogen economy, especially for transportation applications. These electrochemical devices offer significantly higher efficiency compared to conventional heat engines. However, use of exotic and expensive platinum as the electrocatalyst poses serious problems for commercial viability. In this regard, there is an urgent need to develop low-platinum or non-platinum electrocatalysts with electrocatalytic activity for the oxygen reduction reaction (ORR) superior or comparable to that of platinum. This dissertation first investigates non-platinum, palladium-based alloy electrocatalysts for ORR. Particularly, Pd-M (M = Mo and W) alloys are synthesized by a novel thermal decomposition of organo-metallic precursors. The carbon-supported Pd-M (M = Mo, W) electrocatalyts are then heat treated up to 900 oC in H2 atmosphere and investigated for their phase behavior. Cyclic voltammetry (CV) and rotating disk electrode (RDE) measurements reveal that the alloying of Pd with Mo or W significantly enhances the catalytic activity for ORR as well as the stability (durability) of the electrocatalysts. Additionally, both the alloy systems exhibit high tolerance to methanol, which is particularly advantageous for direct methanol fuel cells (DMFC). The dissertation then focuses on one-pot synthesis of carbon-supported multi-metallic Pt-Pd-Co nanoalloys by a rapid microwave-assisted solvothermal (MW-ST) method. The multi-metallic alloy compositions synthesized by the MW-ST method show much higher catalytic activity for ORR compared to their counterparts synthesized by the conventional borohydride reduction method. Additionally, a series of Pt encapsulated Pd-Co nanoparticle electrocatalysts are synthesized by the MW-ST method and characterized to understand their phase behavior, surface composition, and electrocatalytic activity for ORR. Finally, the dissertation focuses on carbon-supported binary Pt@Cu and ternary PtxPd1-x@Cu “core-shell” nanoparticles synthesized by a novel galvanic displacement of Cu by Pt4+ and Pd2+ at ambient conditions. Structural characterizations suggest that the Pt@Cu nanoparticles have a Pt-Cu alloy layer sandwiched between a copper core and a Pt shell. The electrochemical data clearly point to an enhancement in the activity for ORR for the Pt@Cu “core-shell” nanoparticle electrocatalysts compared to the commercial Pt electrocatalyst, both on per unit mass of Pt and per unit active surface area basis. The increase in activity for ORR is ascribed to electronic modification of the outer Pt shell by the Pt-Cu alloy core. However, incorporation of Pd to obtain PtxPd1-x@Cu deteriorates the activity for ORR. / text
538

Solving single variable equations in the algebra classroom

Goodson, Renee Nicole 2009 August 1900 (has links)
This report recognizes the common mistakes students make solving single variable equations and attempts to connect these errors to varying levels of developmental readiness. Striving to meet the needs of all students, this report offers an alternative to lecture based mathematics lessons by exploring the benefits of a unit based curriculum. The unit poses an overarching problem for the students to investigate and answer, while the students still receive the instruction on solving algebraic equations. The goal is to move beyond traditional procedures when solving equations to help students become more familiar with symbol manipulation involved in solving real world story problems. / text
539

Soft spaces

Sanga, Monica, Purnell, Mary 03 September 2014 (has links)
The purpose of this studio was to investigate materiality in the scales of human habitation and to expand traditional notions of architecture through narrative-based design. Narrative-based design is the culmination of studies in the phenomenology of built forms and spatial constructions. It is an experience oriented, democratizing process rather than an image-based, hierarchical process. Using narrative-based design and research on theoretical stances of product manufacturing and interior design we created a domestic space that is an installation. We will built upon Lois Weinthall’s insights regarding the scalar difference between the body, interior design and architecture, and Anni Albers’ theory that the technology of craft should be revealed in the work especially in expressing the nature of the materials used. / text
540

Inquiry-based learning in mathematics : assisting lower ability students with questioning techniques

De Melo, Victor Luis January 2014 (has links)
published_or_final_version / Education / Master / Master of Education

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